1. Field
Advancements in wireless access networks are needed to provide improvements in performance, efficiency, and utility of use.
2. Related Art
Unless expressly identified as being publicly or well known, mention herein of techniques and concepts, including for context, definitions, or comparison purposes, should not be construed as an admission that such techniques and concepts are previously publicly known or otherwise part of the prior art. All references cited herein (if any), including patents, patent applications, and publications, are hereby incorporated by reference in their entireties, whether specifically incorporated or not, for all purposes.
Service Level Agreements (SLAs) are a typical way to sell network bandwidth to wired customers. For example, a customer can have an SLA for (up to) 1.5 Mbps of bandwidth. This bandwidth can be total bandwidth (for upstream or downstream) or can be specified as 1 Mbps downstream (from the Internet/the provider to the customer) and 0.5 Mbps upstream (from the customer to the Internet/provider). Generally an SLA limits the maximum bandwidth a customer will receive but it can additionally specify guaranteed minimum bandwidth that a customer would receive (total or upstream and downstream).
SLAs for bandwidth provisions and guarantees are much easier to support in a wired network than in a wireless network because bandwidth on a wire is constant and can be easily controlled. Wireless bandwidth on the other hand varies in both time and space as propagation conditions vary due to climate, changing obstacles in the vicinity of the network, interfering devices, e.g., microwaves interfere with Wi-Fi signals, and the co-location of multiple wireless networks. Interference and co-location are common, especially when unlicensed bands are used.
Wireless access to network services and the Internet is generally provided through a network of wireless access devices, e.g., base stations (in cellular networks), or Access Points (APs) in WLANs, or by wireless mesh nodes who participate in a mesh network in addition to serving clients. Each wireless access device typically transmits and receives traffic within a particular geographic area where coverage is desired. The combination of areas covered by the individual wireless access devices constitutes the coverage area of the network. Customers typically connect to a wireless access network through their laptops, PDAs, CPE (Customer Premises Equipment) devices, phones, etc. These devices are typically referred to as clients with respect to the network. The base stations/APs are interconnected through a network, which may be wireless or wired, and may also interact with a centralized controller, which may be responsible for controlling some of their behavior and configuration. From now on, we would refer to only APs for simplicity. One example of existing networks of this type is an 802.11-style network.
In a wireless access network serving wireless customers on unlicensed bands, e.g., using the 802.11 family of protocols, hard guarantees are impossible to provide as some devices are not within the control of the network operator, e.g., microwaves, cordless phones, baby monitors. Even 802.11 devices may not be willing or able to comply with SLA policies mandated by a particular network even if they are using the services of that network because they may not have the most up-to-date software. Wireless service networks often have to provide service to such legacy clients in addition to clients that have up-to-date software.
References
The TCP protocol is described in: Postel, J., “Transmission Control Protocol-DARPA Internet Program Protocol Specification”, RFC 793, DARPA, September 1981.
The most up-to-date reference for the 802.11 standard is: IEEE 802.11, 2007 Edition (ISO/IEC 8802-11: 2007) IEEE Standards for Information Technology—Telecommunications and Information Exchange between Systems—Local and Metropolitan Area Network—Specific Requirements—Part 11: Wireless LAN Medium Access Control (MAC) and Physical Layer (PHY) Specification.
All of the aforementioned references are herein incorporated by reference for all purposes.